CHEMIOSMOSIS

• Chemiosmosis is a crucial biological process that plays a fundamental role in cellular energy production, specifically in the synthesis of adenosine triphosphate(ATP).
• Chemiosmosis involves the movement of ions, typically protons (H+), across a selectively permeable membrane, creating an electrochemica gradient, which acts as a driving force for the production of ATP.
• The primary energy carrier in cells.
• Chemiosmosis occurs in both mitochondria and chloroplasts, playing a central role in the production of ATP in cellular respiration and photosynthesis, respectively.
• In mitochondria, chemiosmosis takes place during cellular respiration.
• During the electron transport chain, electrons are passed along a series of protein complexes leading to the pumping of protons (H+) from the mitochondrial matrix into the intermembrane space.
• This creates a proton gradient, with a higher concentration of protons in the intermembrane space compared to the matrix.
• The flow of protons back into the mitochondrial matrix through ATP synthase drives the synthesis of ATP from ADP and inorganic phosphate.
• In chloroplasts, chemiosmosis occurs during photosynthesis.
• During the light-dependent reactions, light energy is used to drive the electron transport chain in the thylakoid membrane, resulting in the pumping of protons from the stroma into the thylakoid space, creating a proton gradient.
• The ATP produced through chemiosmosis serves as the primary energy currency of the cell, providing the necessary energy for various cellular activities such as active transport, biosynthesis, and movement.
• In mitochondria, the high-energy electrons are extracted from the food molecule (from redox reaction).
• In chloroplasts, the source of electrons is from the photons captured from the light source.